关键词: 岩土工程, 拱体, 岩溶地区, 封堵, 应力变形, 封拱温度

Abstract: In order to adapt to the topographic and geomorphological conditions in Karst areas, a new type of arch dam for the closure the bottom of reservoir was developed. And it was necessary to optimize the design of the proposed new type of arch dam. Based on 3D finite element analysis method, the stress deformation of the arch at normal water level, silt load and temperature stress with different factors, such as crown angle, arch end thickness and arch closure temperature were studied. The results show that the tensile stress area of the arch body is mainly distributed at both ends of the long axis. Properly increasing the thickness of the arch end is beneficial to reduce the tensile stress. The stress of the arch can be improved by increasing the angle of the vault properly. With the increase of the angle, the maximum tensile stress and compressive stress of the arch first decrease and then increase, and the optimal vault angle can be obtained in the range of 53.27°~60°. The tensile stress of arch structure increases with the increase of sealing temperature, and it is suggested that the arch sealing construction should be designed at 9 ℃.

Key words: geotechnical engineering, arch dam, Karst area, closure, stress deformation, sealing temperature